ESC module on 90 TT?

[malc350]

Does anyone know where this is located or if it is incorporated in the microfueler?

The other day I got an intermittent code 43 which I diagnosed as a fault with the ESC (Electronic Spark Control). I unplugged the knock sensor and cleaned the contact (not so easy on a TT) but stock 'vettes apparantly have an ESC module located on the outside of the fan motor housing (passenger side). The module is normally too big to miss (!) so I'm guessing TT's either don't have this module or its functions are dealt with by the microfueller or the Callaway chip.

Anyway my code went away so I may have cured it.

 

[EricVonHa]

Malc- Glad to hear the code went away after taking it apart. As far as I'm aware Callaway left the stock electronics intact for the factory computer. The Microfueler functions were sensitive only to RPM and boost conditions and there was no interaction of the Microfueler with the factory ECM. They were 2 separate systems.

If knock were to be detected the GM computer would retard spark timing by itself. One way to lessen the sensitivity of the knock sensor, provided that the code is continually thrown even with a new sensor, is to wrap many turns of teflon tape on the threads and then thread it into the block as far as you can by hand and then put a quarter turn on it with a 22mm socket. Supposedly the further the sensor is turned in to the block-- the more sensitive it becomes.

 

[bill mcdonald]

I have a regular 90, and the ESC is controlled by the ECM that year. It is not located on the fan motor like the 85-89's extrenal ESC.

I had that caode a while back, my knock sensor wire had burned up. I replaced it and everything is fine now.

Anothe rpossible problem could be the knock sensor itself.